/*
 * Copyright 2010 GP Software
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * CsvDataLoader.java | Created on April 25, 2010
 */
package org.gp.gpetl.loader;

import au.com.bytecode.opencsv.CSVReader;
import org.gp.gpetl.exception.DataLoadingException;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.List;

/**
 * Loads data from a CSV file source
 *
 * @author Paul Augustine C. Mendoza
 * @since 1.0
 */
public class CsvDataLoader implements DataLoader {

    /**
     * @see DataLoader#load(Object)
     */
    public List<String[]> load(Object source) throws DataLoadingException {
        File input = (File) source;
        List<String[]> data = null;
        CSVReader reader = null;
        if (input == null) {
            throw new IllegalArgumentException(
                    "File input should not be null.");
        }
        try {
            reader = new CSVReader(new FileReader(input), ',',
                    '\'');
            data = reader.readAll();
        } catch (FileNotFoundException e) {
            throw new DataLoadingException(e, input);
        } catch (IOException e) {
            throw new DataLoadingException(e, input);
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return data;
    }
}
